In integrated circuit (IC) manufacturing, electronic devices fabricated on a semiconductor substrate (transistors, for example) typically require the formation of electrical connections between one another in order to form the desired final operational IC device. This connection process is generally referred to as “metallization,” and it may be performed using a number of photolithographic patterning, etching, and deposition techniques and steps. Typically, metallization results in the filling with one or more conductive materials of the various interconnect structures formed in the surface of a semiconductor substrate, which after fill may then function as electrical pathways to interconnect the various circuit devices on the substrate. For example, tungsten, copper, and/or other conductive materials may be used for filling horizontal interconnects, vias between adjacent metal layers, contacts between first metal layers and devices on the silicon substrate, and may generally be used for filling various high aspect ratio features utilized in IC design.